I hope someone knows the answer to my question.

When I really feel the need to wee I go to the toilet. Sometimes I wee a lot, sometimes I wee a medium amount, sometimes I wee relatively little. What exactly is it that creates the feeling of needing to wee? Clearly it can't be bladder fill-volume because there are times when you can hold in a massive amount without really feeling desperate and there are times when you feel like you really need to go and there's almost nothing there. Is it a function of hydration? Kidney flow (rate of urine production)? Some hormone level? Anyone know?

clop

Hey Clop. One of the things you have to realize is you bladder is not a jar. Its a muscular sac. So its empty volume is not constant. Sometimes for various reasons the muscles making up your bladder contract down on the contents giving you that urge to go.

I'm in and out of the hospital a lot and have to lay in bed hooked to IV lines. Those make you go alot and when really full my bladder has a volume of 1.3 liters. Have to ask the nurse for two urinals to finish my business. (They only hold a liter.) Plus your bladder will die and become necrotic if you don't empty it at least every 24 hours but that usually only happens to folks in comas and the elderly.

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"The beauty of that discussion of averages is that you don't have to be an expert in Apollo or in photography in order to see where this time study "analysis" breaks down. You just have to be, well...not an idiot." -JayUtah

Thanks BigDon but that doesn't seem to explain it completely. I know that on a Sunday when I drink a few cups of tea during the day I tend to go for a wee much more frequently than usual, with the typical sense of needing to go, but with a lower than normal volume each time. And sometimes, if I know that I will not have access to a toilet for several hours, I can switch off the feeling of needing to wee almost indefinitely, but if there is the anticipation of soon using a toilet, I'm instantly desperate. Even if I know I can last for another hour, as soon as I'm within sight of the toilet I have to hurry.

clop

I have noticed what you mention, but I don't really have an answer for it. I used to try and go by time. Could I fit a bio brak in during a commercial break. As it turns out the average for me is a bit over 1 minute, though one time I did have a Legue of Their Own moment.

The one I've noticed more often and wondered about is the Movie Theater Experience. I make it a point to visit the bathroom right before seating at a movie. I rarely get anything bigger than a 32 oz drink, even though it's only a quarter to get the Bladder Buster 9000 that comes with it's own Sherpa to get it to your seat, but by the time I've sat there for 2.5 hours, I'm in a crisis. It doesn't happen on car trips when I sit for much longer and consume more fluids.

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A Nerd can figure out how long it will take the original Enterprise traveling at warp 6.5 to travel from Regulus to Antares.
A Geek will think he can use that to pick up a girl in a bar.
A Dork knows he can't pick up the girl with it, but will hang around for hours anyway, just in case she asks.
She might. You never know.

I heard a roofing carpenter say that when he did roofs(many years ago) he could drink lots all day(on a hot day) and didn't need to go to the toilet, he just sweated it all off.

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Brian's mother: He's not the Messiah. He's a very naughty boy!

Frog, I'm a furniture mover in California. I can vouch for your friends claim. I do the exact same thing in theatres, Tog. It must be the airconditioning keeping you from sweating so our kidneys have to do all the work. Just a guess.

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"The beauty of that discussion of averages is that you don't have to be an expert in Apollo or in photography in order to see where this time study "analysis" breaks down. You just have to be, well...not an idiot." -JayUtah

Frog, one night on the fright crew (grocery store stocking) we had a big load and were down a guy. I sweated a lot that night and drank a full 1/2 gallon of orange juice on the way home. I didn't need to use the bathroom for 14 more hours.

My theory on the movie was that you don't actually sweat, but the movie still causes your heart to beat faster due to 'putting yourself in the action' so everything that comes with being active happens except the sweat and getting in shape. That theory was utterly destroyed by End of the Affair, Becasue I still had to go after sitting through all 437 percieved hours of it.

It had Stephen Rea in it, so the GF made me go.

Edit to add, one slice of watermelon OR a sunburn will make go nearly every hour for at least a day.

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A Nerd can figure out how long it will take the original Enterprise traveling at warp 6.5 to travel from Regulus to Antares.
A Geek will think he can use that to pick up a girl in a bar.
A Dork knows he can't pick up the girl with it, but will hang around for hours anyway, just in case she asks.
She might. You never know.

Couple of things in action here, I think.
One is that your bladder feeds back to your brain not just the current volume of urine, but also the rate of filling: so you get the urge to empty at lower volumes if your bladder's filling fast.
The other is that, of course, there's descending inhibition from your brain to your bladder, and that's influenced by your conscious mind to a large extent. So you actually modulate the amount of bladder sensation that gets through to consciousness, depending on the availability of opportunities to empty: if you're far from a toilet, or really busy, the signal drops into the background unless things get really urgent. But if you find yourself in a situation in which you can empty your bladder, the signal comes back. Hence the feeling of sudden urgency when you reach the bathroom door.
Another thing I find interesting is how the sound of running water can trigger the urge to empty. Is that an evolutionary thing? Perhaps urinating in a place where there's running water was a good way to avoid contaminating your sleeping or living area. It's not just water ... the sound of a petrol tank filling will do it for me, too.

Grant Hutchison

...and then there's the old "hand in warm water" trick, best used on the sleeping.

This could be because tea, coffee and alcohol are diuretics i.e. they make you go to the toilet more often. I presume that means you'll go sooner, with a smaller amount, although the net result is to make you more dehydrated.

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Spike
:)

A good indicator of the hydration level is the color of the urine. Generally a clear urine indicates an adequate hydration [my doc just told me that]. It´s an important info for those who´re living dog days.

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"Shut up and calculate" R. Feynman

I had several kidney stones about ten years ago, and as a result I'm nuts about staying hydrated. Whenever my urine turns yellow, I start chugging water like mad.

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Everything I need to know I learned through Googling.

Yeah, it does seem to work. I'm not sure if anyone has a clue why that should be.

Another problem reported by divers is the process of getting into a wetsuit, getting into the ocean, and having a full bladder half an hour later. That one turns out not to be all in the head: there's real physiology involved. When you get into the water, the pressure compresses your limbs and moves blood from where it usually hangs about in the peripheral veins, into your chest and abdomen. Your body interprets this as a sudden mysterious fluid overload, and industriously sets about getting rid of fluid through your kidneys.

Grant Hutchison

I wonder if it the sitting. I've noticed that sitting in a meeting I seem to need to go more frequently than if I'm running around the plant, no matter what the temperature and the amount of sweating. Maybe various positions puts more pressure on the bladder, sort of like the diver stuff Grant mentioned. Or maybe it is the opposite of what Grant mentioned in his earlier post - not the opportunity to go, but the lack of opportunity. Whenever you are stuck someplace, like in a meeting, it always seems worse.

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At night the stars put on a show for free (Carole King)

The ren faire rule is that, if you lose all your moisture through sweat and don't need to pee, you're not intaking enough fluids. We take dehydration very seriously, especially given how many of the patrons don't. We'd like to have as few paramedics on duty on site as possible.

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Gillian

"Now everyone was giving her that kind of look UFOlogists get when they suddenly say, 'Hey, if you shade your eyes you can see it is just a flock of geese after all.'"

"You can't erase icing."

"I can't believe it doesn't work! I found it on the internet, man!"

Hi Clop,

If this is concerning you on a personal level, I'd make an appointment with your doctor and have it checked out. If a urologist had answered your post, I'm sure that's what he/she would have told you.

Luckmeister

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Why the avatar grin? I'm watching my favorite actress/model through my 4D glasses -- it sure beats looking at a tesseract.

Same with the SCA. The have Water Bearers and Chirurgeons (basically, our version of paramedics).

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"A long habit of not thinking a thing wrong gives it a superficial appearance of being right." -- Thomas Paine

Being intelligent is not a felony. But most societies evaluate it as at least a misdemeanor. -- Heinlein

Creationists make it sound as though a "theory" is something you dreamt up after being drunk all night. -- Isaac Asimov

Indeed. Around here, it's basically the same bunch of people at faire and at SCA events.

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Gillian

"Now everyone was giving her that kind of look UFOlogists get when they suddenly say, 'Hey, if you shade your eyes you can see it is just a flock of geese after all.'"

"You can't erase icing."

"I can't believe it doesn't work! I found it on the internet, man!"

Yeah, I think it's the attentional thing in reverse. If you're busy and distracted and the opportunity isn't there, you down-modulate the bladder signal. If you're bored and you think about it, you're doomed.

Grant Hutchison

Speaking of which, I took a waterbearing and chirurgeon class, both 101, for the SCA.

Apparently, alcohol and peroxide are bad for treating wounds; use soap and water. Alcohol and peroxide might disinfect, but they also prevent the clotting of blood. There are various other things, too, but I found it interesting that some people out there are entirely allergic to Citrus, in a deathly way; we have one such person in our Kingdom. So we have to be extra careful to cut the pickles and the oranges seperately for waterbearing.

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"A long habit of not thinking a thing wrong gives it a superficial appearance of being right." -- Thomas Paine

Being intelligent is not a felony. But most societies evaluate it as at least a misdemeanor. -- Heinlein

Creationists make it sound as though a "theory" is something you dreamt up after being drunk all night. -- Isaac Asimov